A Pilot Study on the Biological Treatment of PTA Wastewater with Functional Strain Fhhh

Abstract

The functional strain Fhhh, constructed with the protoplast fusion technique, was applied to PTA wastewater treatment at a NJYZ pilot plant. The maximum chemical oxygen demand (COD) removal efficiency and effluent suspended solids obtained were 97% and 59 mg L−1, respectively, at a hydraulic retention time of 1.3 days and an F/M rate of 1.35 g COD g SS−1 day−1. The specific degradation rate arrived at 1.31 day−1 in the bioreactor after a 180-day operation, which is much higher than corresponding data of other related references. The addition of Mn2+, Cu2+, Zn2+, and SeO3 2− significantly stimulated the MnP exprssion, and a positive correlation was established between the improvement of MnP expression and the removal efficiencies of COD, tereogtgaleuc acid, p-toluic acid, and 4-carboxybenzaldehyde in purified terephthalic acid wastewater. The effluent water quality was also improved significantly as long as the COD:TN:TP ratio was optimally maintained around 100:1.16:0.22; the best growth and flocculation performance were obtained with a specific growth rate of 0.133 day−1 and sludge volume index of 136 mL g−1.